Access floor assembly with access floor panels having interlocking edges

ABSTRACT

An access floor panel assembly including (1) a plurality of access floor panels arranged edge-to-edge and (2) a plurality of spaced pedestals. The plurality of access floor panels are positioned above a subfloor by the plurality of pedestals. Each of the plurality of access floor panels includes (1) a support layer and a floor finish layer on top of the support layer and (2) four edges. At least one of the four edges has a tongue connector or a groove connector, which are configured to form a tongue and groove connection when joined. Each of the tongue connector and each of the groove connector is formed by the support layer and the floor finish layer.

FIELD OF INVENTION

This invention relates to access floor assemblies. More specifically, this invention relates to access floor assemblies that include access floor panels with interlocking edges.

BACKGROUND OF INVENTION

Access floors are utilized in many applications, including, but not limited to, data rooms or centers, office floor space and clean rooms. Typical access floors include a continuous array of access floor panels arranged edge-to-edge and supported by pedestals above a subfloor, to provide a passageway between the subfloor and the plurality of access floor panels for cables, wiring, cooling air, etc. The continuous array of access floor panels usually extends wall-to-wall in the room or facility that includes the access floor. In most access floor assemblies, all the access floor panels are individually removable to gain access to the passageway between the access floor panels and the subfloor via removal of any of the panels. However, there are some applications of access floors in which having each access floor panel be individually removable is undesirable. The reasons why it is undesirable to have each access floor panel be removable in such applications include the requirement for security in the room or facility including the access floor (so that access cannot be gained by lifting one of the access floor panels from below), to prevent liquids from passing between adjacent access floor panels into the passageway between the access floor panels and the subfloor, and the need for a very smooth and level floor. Such applications may include airports, hospitals and retail establishments.

In view of the above, it is desirable to provide an access floor assembly constructed such that not all of the individual access floor panels are removable.

SUMMARY OF INVENTION

The access floor assemblies of this invention address the above need and other needs that will be apparent to those skilled in the art upon review of this disclosure.

An access floor assembly according to one embodiment of this invention includes a plurality of access floor panels arranged edge-to-edge and a plurality of pedestals. The plurality of access floor panel is positioned above a subfloor by the plurality of pedestals. In this embodiment of the invention, each of the plurality of access floor panels includes (1) a support layer and a floor finish layer on top of the support layer and (2) four edges. At least one of the four edges has a tongue connector or a groove connector. The tongue connector and the groove connector are configured to form a tongue and groove connection when joined. Each of the tongue connector and each of the groove connector are formed by the support layer and the floor finish layer.

In another embodiment of the invention, the floor finish layer is the top layer of each of the plurality of access floor panels.

In other embodiments of the invention, a first set of the plurality of access floor panels has the groove connector on the four edges and a second set of the plurality of access floor panels has the tongue connector on the four edges.

In certain other embodiments of the invention, each of the plurality of access floor panels has two edges with the tongue connector and two edges with the groove connector.

In further embodiments of the invention, the two edges with the tongue connector are perpendicular and form a first corner of each of the plurality of access floor panels, and the two edges with the groove connector are perpendicular and form a second corner of each of the plurality of access floor panels.

In yet other embodiments of the invention, the tongue connector includes a side wall and a tongue that extends outwardly from the side wall, and the tongue includes part of the support layer and part of the floor finish layer.

In additional embodiments of the invention, the tongue connector includes a side wall and tongue that extends outwardly from the side wall, and the tongue is formed only by the support layer and the side wall is formed by the support layer and the floor finish layer.

In yet other embodiments of the invention, the groove connector includes a side wall and a groove recessed inwardly from the side wall, the groove has a top surface, a back wall and a bottom surface, and the back wall of the groove is formed in part by the support layer and in part by the floor finish layer.

In yet other embodiments of the invention, the groove connector includes a side wall and a groove recessed inwardly from the side wall, the groove has a top surface, a back wall and a bottom surface, the back wall and the bottom surface of the groove are formed by the support layer, and the top surface of the groove is formed by a bottom surface of the floor finish layer.

The invention also includes a method of forming an access floor assembly that includes the steps of (1) placing spaced supporting pedestals on a subfloor in an array of perpendicular rows, (2) placing understructure members on the pedestals such that the understructure members extend between and are supported by the pedestals, (3) placing a plurality of access floor panels on the substructure members edge-to-edge, each of the plurality of access floor panels includes (a) a support layer and a floor finish layer on top of the support layer and (b) four edges, at least one of the four edges has a tongue connector or a groove connector, the tongue connector and the groove connector are configured to form a tongue and groove connection when joined, each of the tongue connector and the groove connector is formed by the support layer and the floor finish layer, wherein the plurality of access floor panels are positioned such that the groove connectors of a first set of a plurality of access panels face the tongue connectors of a second set of the plurality of access floor panels, and (4) inserting the tongue connectors into the groove connectors.

The advantages of this invention include at least the following. The top surface of the access floor assemblies of this invention is a smooth, joint-less surface that may result in superior walking comfort, increased stability, and the prevention of fluids passing between adjacent access floor panels into the passageway between the access floor panels and the subfloor. Also, this invention results in an access floor assembly with access floor panels that are difficult to remove individually, which increases the security of the room or facility that includes the access floor assembly, as discussed above. Further, each of the access floor panels of this invention includes the support layer and the floor finish layer. The inclusion of the support layer and the floor finish layer in each access floor panel means that only one layer of access floor panels has to be installed, which reduces the installation time and costs when compared to the previous access floor panels with interlocking edges that consist only of the support layer. The formation of an access floor assembly using the previous interlocking panels involves at least two steps—first install a layer of support panels with interlocking edges and then install a floor finish layer on top of the layer of support panels.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an elevation view of one embodiment of this invention.

FIG. 2 is a plan view of the understructure and pedestals of the embodiment of this invention illustrated in FIG. 1.

FIG. 3 is an elevation view of one of the access floor panels and one of the pedestals of the embodiment of this invention illustrated in FIG. 1.

FIG. 4 is a plan view of one embodiment of an access floor panel that can be used in the embodiment of this invention illustrated in FIG. 1.

FIG. 5 is a plan view of a second embodiment of an access floor panel that can be used in the embodiment of this invention illustrated in FIG. 1.

FIG. 6 is a plan view of a third embodiment of an access floor panel that can be used in the embodiment of this invention illustrated in FIG. 1.

FIG. 7 is a cross-sectional view of the access floor panel illustrated in FIG. 4, taken along line 7-7 of FIG. 4.

FIG. 8 is a cross-sectional, elevation view of a fourth embodiment of an access floor panel that can be used in the embodiment of this invention illustrated in FIG. 1.

FIG. 9 is a cross-sectional view of the access floor panel illustrated in FIG. 5, taken along the line 9-9 of FIG. 5.

FIG. 10 is a cross-sectional, elevation view of a fifth embodiment of an access floor panel that can be used in the embodiment of this invention illustrated in FIG. 1.

FIG. 11 is a cross-sectional view of the access floor panel illustrated in FIG. 6, taken along line 11-11 of FIG. 6.

FIG. 12 is a cross-sectional, elevation view of a sixth embodiment of an access floor panel that can be used in the embodiment of this invention illustrated in FIG. 1.

FIG. 13 is an elevation view of parts of two of the access floor panel illustrated in FIG. 8, aligned such that an edge of one of the two panels having a tongue connector faces an edge of the other of the two panels having a groove connector, with (1) caulk/glue applied to the tongue connector of the one of the two panels and (2) an adhesive applied to the groove connector of the other of the two panels.

FIG. 14 is an elevation view of the parts of the two panels of FIG. 13 after the two panels are brought together edge-to-edge such that the tongue connector of the one of the two panels engages the groove connector of the other of the two panels.

FIG. 15 is an elevation view of the parts of the two panels of FIGS. 13 and 14 after the two panels have been brought together and the tops of the two panels have been honed to remove any excess caulk, glue and/or adhesive.

FIG. 16A is an elevation view of the parts of two panels of a seventh embodiment of the access floor panels that can be used in the access floor assemblies of this invention, aligned such that an edge of one of the two panels having a tongue connector faces, but is spaced from, an edge of the other of the two panels having a groove connector.

FIG. 16B is another elevation view of the parts of the two panels illustrated in FIG. 16A showing the tongue connector in engagement with the groove connector.

FIG. 17 is a plan view of the understructure of another embodiment of this invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS ILLUSTRATED IN THE FIGURES

As stated, one embodiment of an access floor assembly of this invention is illustrated in FIG. 1, access floor assembly 21. Access floor assembly 21 includes array of access floor panels 23, understructure 25 and pedestals 27. Array of access floor panels 23 is comprised of a plurality of access floor panels 43 arranged edge-to-edge.

Pedestal 27 is one example of the pedestals that can be employed in the access floor assemblies of this invention. Other known pedestals can be used instead of, or with, pedestals 27.

As illustrated in FIGS. 1, 3 and 15, pedestal 27 includes base plate 29, which is designed and configured to rest on a subfloor, such as subfloor 22, upright receptacle 31, which is affixed to and extends upward from base plate 29 and has internal threads, top plate 33 and threaded member 35, which is affixed to and extends downward from top plate 33 and is threadedly received in upright receptacle 31.

The height of top plate 33 relative to base plate 29 (and thus to subfloor 22) can be adjusted by the threaded engagement of threaded member 35 and upright receptacle 31.

In this embodiment of the invention, understructure 25 includes main supports 37, cross supports 39, and weld plates 41. Other configurations of understructure can be utilized as long as the understructure provides the necessary interface between the pedestals and the access floor panels.

Understructure 25 is configured as follows.

As illustrated in FIG. 2, in this embodiment of the invention, main supports 37 are arranged in parallel rows, end-to-end within each row, and extend between and are connected at their ends to top plates 33 of two pedestals 27. In this configuration of understructure, each main support 37 spans three pedestals 27. That is, both ends of each main support 37 are attached to a pedestal 27 and each main support 37 is also attached at its mid-span to another pedestal 27 that is located midway between the two pedestals 27 at the ends of each main support 37.

In other embodiments of the invention, each main support may span only two pedestals and be connected at its ends to those two pedestals. In yet other embodiments of the invention, each main support may span more than three pedestals. In further embodiments of this invention, the lengths of the main supports in a given understructure may vary. For example, some of the main supports may span two pedestals, while other main supports may span three or more pedestals.

Main supports 37 are attached to top plates 33 of pedestals 27 by welding, bolts and/or any other acceptable attachment method or means.

In this understructure configuration, cross supports 39 are oriented perpendicular to the rows of main supports 37. Cross supports 39 are of two types. The first type extends between and is connected on their ends to top plates 33 of adjacent pedestals 27. The second type extends between and is connected on their ends to adjacent main supports 37 by weld plates 41. As can be seen in FIG. 2, the first type and the second type are arranged in alternating rows, perpendicular to the rows of main supports 37. Like main supports 37, cross support 39 can be attached to top plates 33 of pedestals 27 by welding, bolts and/or any other acceptable attachment method or means. Similarly, weld plates 41 can be attached to main supports 37 and cross supports 39 by welding, bolts and/or any other acceptable attachment method or means.

In this embodiment of the invention, main supports 37 and cross supports 39 form a grid, from the plan perspective, such that edges of access floor panels 43 are directly supported by main supports 37 and cross supports 39. More specifically, main supports 37 and cross supports 39 supports all the edges of the access floor panels 43 of array of access floor panels 23 that are “interior panels”, i.e., panels that do not form an edge of array of access panels 23. For access floor panels 43 that form, in part, an edge of array of access floor panels 23, the edges of those panels that do not form an edge of array of access floor panels 23 are also directly supported by main supports 37 and cross supports 39.

As illustrated in FIGS. 1, 2 and 15, main supports 37 and cross supports 39 are, in this embodiment of the understructure of this invention, box beams. In other embodiments, main supports 37 and cross supports 39 can be any type of compatible structural members, including I-beams, channels, etc.

As stated, one embodiment of an access floor panel that can be used in array of access floor panels 23 is illustrated in FIGS. 4 and 7, access floor panel 45. Access floor panel 45 has edges 46-49. Edges 46 and 47 form tongue connectors, and edges 48 and 49 form groove connectors. More specifically, edges 46 and 47 have tongue 50 that extends outwardly from side walls 51 and 52. Side walls 51 and 52 are in a common plane. Edges 48 and 49 have groove 53 that is recessed from side walls 54 and 55. Side walls 54 and 55 are in a common plane. Tongues 50 and grooves 53 are configured such that tongues 50 are received in grooves 53.

While, in access floor panel 45, side walls 51 and 52 are in a common plane and side walls 54 and 55 are in a common plane, in other embodiments of the access floor panels that can be used in this invention, side wall 52 could be offset from side wall 51 and side wall 55 could be offset from side wall 54.

Access floor panel 45 also includes support layer 57 and floor finish layer 59. See FIG. 7. Floor finish layer 59 is affixed to the top of support layer 57, and is usually a decorative layer.

As can be seen in FIG. 7, the bottom surface of floor finish layer 59 forms the top surfaces of the grooves of edges 48 and 49, including top surface 60 of groove 53 in edge 49. The back walls and bottom surfaces of the grooves, including groove 53, are formed by support layer 57. The tongues of edges 46 and 47, including tongue 50 of edge 47, are formed entirely by support layer 57. The top surface of support layer 57 forms the top surfaces of the tongues, including top surface 58 of tongue 50.

Another embodiment of an access floor panel that can be used in array of access floor panels 23, and having, like access floor panel 45, two edges forming tongue connectors and two edges forming groove connectors, but with different thicknesses of the support layer and the floor finish layer, is illustrated in FIG. 8, access floor panel 45′. Access floor panel 45′ has four edges, including edges 47′ and 49′, support layer 57′ and floor finish layer 59′, illustrated in FIG. 8. As stated, two of the edges, including edge 47′, form tongue connectors that include a tongue, such as tongue 50′ in FIG. 8. The other two edges of access floor panel 45′, including edge 49′, form groove connectors that include a groove, such as groove 53′ in FIG. 8. In access floor panel 45′, unlike access floor panel 45, floor finish layer 59′ forms part of the back walls of the grooves, including groove 53′, and the top surfaces of the tongues, including top surface 58′ of tongue 50′, is formed by floor finish layer 59′.

Another embodiment of an access floor panel that can be used in array of access floor panels 23 is access floor panel 61, illustrated in FIGS. 5 and 9. Access floor panel 61 has edges 62-65, support layer 68 and floor finish layer 69. Each of edges 62-65 forms a tongue connector. Each tongue connector has a tongue, such as tongues 66 and 67 on edges 62 and 64, respectively, as illustrated in FIG. 9. As also illustrated in FIG. 9, the tongues, including tongues 66 and 67, consist entirely of support layer 68. The top surface of support layer 68 forms the top surfaces of the tongues, including top surfaces 82 and 83 of tongues 66 and 67, respectively.

Another embodiment of an access floor panel that can be used in array of access floor panels 23, and having, like access floor panel 61, tongue connectors along its four edges, but with different thicknesses of the support layer and the floor finish layer, is illustrated in FIG. 10, access floor panel 61′. Access floor panel 61′ has four edges, including edges 62′ and 64′, support layer 68′ and floor finish layer 69′, as illustrated in FIG. 10. In access floor panel 61′, unlike access floor panel 61, the tongues of the tongue connectors, such as tongues 66′ and 67′, are formed in part by support layer 68′ and in part by floor finish layer 69′, and top surfaces 82′ and 83′ of tongues 66′ and 67′, respectively, are formed by floor finish layer 69′.

Another embodiment of an access floor panel that can be used in array of access floor panels 23 is access floor panel 70, illustrated in FIGS. 6 and 11. Access floor panel 63 has edges 71-74, support layer 75 and floor finish layer 76. Each of edges 71-74 forms a groove connector. Each groove connector has a groove, such as grooves 77 and 78 on edges 71 and 73, respectively, illustrated in FIG. 11. As also illustrated in FIG. 11, the back wall of the grooves, including of grooves 77 and 78, are formed entirely by support layer 75 and the top surfaces of the grooves, including top surfaces 79 and 80 of grooves 77 and 78, respectively, are formed by the bottom surface of floor finish layer 76.

Another embodiment of an access floor panel that can be used in array of access floor panels 23, and having, like access floor panel 70, groove connectors along its four edges, but with different thicknesses of the support layer and the floor finish layer, is illustrated in FIG. 12, access floor panel 70′. Access floor panel 70′ has four edges, including edges 71′ and 73′, support layer 75′ and floor finish layer 76′, as illustrated in FIG. 12. In access floor panel 70′, unlike access floor panel 70, the back walls of the grooves, including of grooves 77′ and 78′, are formed in part by floor finish layer 76′ and in part by support layer 75′.

Support layers 57, 57′, 68, 68′, 75 and 75′ can be comprised of a concrete formed from a mixture of cement, water, limestone aggregate and haydite, or any other materials suitable for use as support layers for access floor panels. Floor finish layers 59, 59′, 69, 69′, 76 and 76′ can be comprised of concrete formed from a mixture of cement, water, limestone aggregate, concrete sand, marble dust, and a colored pigment, a concrete formed from a mixture of cement, water and marble aggregate, or any other materials suitable for use as a floor finish layer of access floor panels.

In certain embodiments of the access floor panels that can be used in this invention, a steel sheet can be attached to the bottom surface of the support layer and/or steel edging can be attached to one or more of the side edges of the access floor panels.

Another embodiment of access floor panels that can be used in array of access floor panel 23 includes access floor panels 101 and 102, illustrated in FIGS. 16A and 16B.

Access floor panel 101 includes at least one edge 103 that forms a tongue connector having a tongue 105. Access floor panel 102 includes at least one edge 104 that forms a groove connector having groove 106. Tongue 105 is received within groove 106 when access floor panels 101 and 102 are joined edge-to-edge.

Unlike the tongues of the other embodiments of access floor panels of this invention illustrated in FIGS. 7-15 and described above, in which the top and bottom surfaces of the tongues are equal depth, top surface 107 of tongue 105 is “deeper” than bottom surface 108. Thus, as shown in FIG. 16B, when tongue 105 is inserted into groove 106, and groove 106 has upper and lower surfaces of same depth, gap 109 is formed between upper wall 110 of edge 103 and upper wall 111 of edge 104. Grout can be applied in gap 109 as desired.

Array of access floor panels 23 can consist of the following: (1) a plurality of access floor panels 45; (2) a plurality of access floor panels 45′; (3) a plurality of access floor panels 61 in combination with a plurality of access panels 70; (4) a plurality of access floor panels 61′ in combination with a plurality of access floor panels 70′; or a plurality of panels 101 and 102.

Access floor assembly 21 can be assembled as follows.

Pedestals 27 are positioned on a subfloor, such as subfloor 22, with base plates 29 of pedestals 27 resting on the sub-floor. Base plates 29 can simply rest on subfloor 22, or they can be attached to subfloor 22 by adhesive or any other acceptable attachment method or means. Pedestals 27 are arranged on subfloor 22, spaced apart, and in perpendicular rows, as illustrated in FIG. 2.

The desired height of top plate 33 of each pedestal 27, vis-à-vis sub-floor 22, is achieved by rotating the threaded member 35 of each pedestal within its upright receptacle 31.

Main supports 37 are then positioned on top plates 33 of pedestals 27 to form the parallel rows of main supports 37 illustrated in FIG. 2. As stated above, in this embodiment of the invention, each main support 37 spans three pedestals 27, with each end of each main support 37 being supported by and connected to a pedestal 27, and the mid-span of each main support 37 also being supported by and connected to yet another pedestal 27. As also stated above, main supports 37 may be attached to top plates 33 of pedestals 27 by welding, bolts and/or any other acceptable attachment method and means known in the industry.

Next, cross supports 39 are attached to pedestals 27 and main supports 37. In the array of understructure 25 illustrated in FIG. 2, a first set of cross supports 39 is attached on their ends to top plates 33 of pedestals 27 and a second set of cross supports 39 is attached on their ends to main supports 37 by weld plates 41. As stated, cross supports 39 are attached to top plates 33 of pedestals 27 and to weld plates 41, and weld plates 41 are attached to main supports 37, by welding, bolts and/or any other acceptable attachment method or means.

FIG. 2 illustrates one configuration of pedestals 27, main supports 37, cross supports 39 and weld plates 41 that can be used in access floor assembly 21. Any array of those components, or of similar components, can be utilized as long as the array of access floor panels 23 is sufficiently supported.

A plurality of access floor panels is then placed on main supports 37 and cross supports 39 and connected on their edges to form array of access floor panels 23. One method of doing so is illustrated in FIGS. 13-15, which illustrate one way to connect two access floor panels 45′ edge-to-edge.

As shown in FIG. 13, with the two access floor panels 45′ separated, caulk/glue 65 is applied to the upper surface of tongue 50′ of one of the access floor panels 45′. Caulk/glue 65 may be colored to coordinate with the floor finish layer 59′ of access floor panel 45′. Adhesive 66 is applied to the bottom surface of groove 53′ of the other access floor panel 45′.

Next, as shown in FIG. 14, one or both of the access floor panels 45′ are moved laterally such that tongue 50′ is received in groove 53′. The joined edges are directly supported by a main support 37 (or a cross support 39). A combination of caulk/glue 65 and adhesive 66 fills the space between the facing edges of the two access floor panels 45′. In addition, some of caulk/glue 65 and adhesive 66 may “squeeze out” from the space between the facing edges of the two access floor panels 45′, both above the top surfaces and below the bottom surfaces of the access floor panels 45′.

The top surfaces of access floor panels 45′ may be honed to remove any caulk/glue 65 and/or adhesive 66 that protrude above the top surfaces of panels 45′. The end result is illustrated in FIG. 15. Excess caulk/glue 65 and adhesive 65 that protrudes below the bottom surfaces of access floor panels 45′ may adhere the two access floor panels 45′ to a main support 37 (or a cross support 39), as illustrated in FIG. 15.

Finally, the top surfaces of access floor panels 45′ may be polished and sealed as desired.

In some applications, it may not be necessary or desirable to use caulk, glue and/or an adhesive between the joined edges.

As stated, the configuration of the understructure of another embodiment of this invention is illustrated in FIG. 17. The primary difference between this understructure configuration and the understructure configuration illustrated in FIG. 2 is that, in this configuration, cross supports 113 are aligned in continuous rows, while, in the FIG. 2 configuration, cross supports 39 are in interrupted rows, i.e., there is a “gap” of one panel between every two cross supports 39 in a given row. In this configuration, there is no need for weld plates, such as weld plates 41, because all ends of cross supports 113 will be attached to a pedestal.

What is described and illustrated herein are preferred embodiments of the invention. The terms, descriptions and figures are set forth by way of illustration only and are not intended and meant to be limitations. Those skilled in the art will recognize that many other embodiments and variations of the invention are possible, which invention is defined by the following claims in which all terms are intended and meant in their broadest reasonable meaning unless otherwise indicated. 

1. An access floor assembly comprising: a plurality of access floor panels arranged edge-to-edge; and a plurality of pedestals; wherein: each of the plurality of access floor panels includes (1) a support layer and a floor finish layer on top of the support layer and (2) four edges; at least one of the four edges has a tongue connector or a groove connector; the tongue connector and the groove connector are configured to form a tongue and groove connection when joined; each of the tongue connector and each of the groove connector is formed by the support layer and the floor finish layer; and the plurality of access floor panels are positioned above a subfloor by the plurality of pedestals.
 2. The access floor assembly according to claim 1, wherein the floor finish layer is a top layer of the each of the plurality of access floor panels.
 3. The access floor assembly according to claim 1, wherein: a first set of the plurality of access floor panels has the groove connector on the four edges; and a second set of the plurality of access floor panels has the tongue connector on the four edges.
 4. The access floor assembly according to claim 1, wherein each of the plurality of access floor panels has two edges with the tongue connector and two edges with the groove connector.
 5. The access floor assembly according to claim 4, wherein: the two edges with the tongue connector are perpendicular and form a first corner of the each of the plurality of access floor panels; and the two edges with the groove connector are perpendicular and form a second corner of the each of the plurality of access floor panels.
 6. The access floor assembly according to claim 1, wherein: the tongue connector includes a side wall and a tongue that extends outwardly from the side wall; and the tongue includes part of the support layer and part of the floor finish layer.
 7. The access floor assembly according to claim 1, wherein: the tongue connector includes a side wall and a tongue that extends outwardly from the side wall; the tongue is formed by only the support layer; and the side wall is formed by the support layer and the floor finish layer.
 8. The access floor assembly according to claim 7, wherein: a top surface of the tongue is formed by a top surface of the support layer.
 9. The access floor assembly according to claim 1, wherein: the groove connector includes a side wall and a groove recessed inwardly from the side wall; the groove has a top surface, a back wall and a bottom surface; and the back wall of the groove is formed in part of the support layer and in part of the floor finish layer.
 10. The access floor assembly according to claim 1, wherein: the groove connector includes a side wall and a groove recessed inwardly from the side wall; the groove has a top surface, a back wall and a bottom surface; and the back wall and the bottom surface of the groove are formed by only the support layer; and the top surface of the groove is formed by a bottom surface of the floor finish layer.
 11. The access floor assembly according to claim 1, further comprising understructure positioned between the plurality of access floor panels and the pedestals; wherein the understructure extends between and is supported by the pedestals and the four edges of the each of the plurality of access floor panels rest on the understructure.
 12. A method of forming an access floor assembly comprising the steps of: placing spaced supporting pedestals on a subfloor in an array of perpendicular rows; placing understructure members on the pedestals such that the understructure members extend between and are supported by the pedestals in perpendicular rows; placing a plurality of access floor panels on the understructure members edge-to-edge, each of the plurality of access floor panels includes (1) a support layer and a floor finish layer on top of the support layer and (2) four edges, at least one of the four edges has a tongue connector or a groove connector, the tongue connector and the groove connector are configured to form a tongue and groove connection when joined, each of the tongue connector and each of the groove connector is formed by the support layer and the floor finish layer, wherein the plurality of access floor panels are positioned such that the groove connectors of a first set of the plurality of access floor panels face the tongue connectors of a second set of the plurality of access floor panels; and inserting the tongue connectors into the groove connectors.
 13. The method of forming an access floor assembly according to claim 12, further comprising the step of applying an adhesive to the groove connectors of the first set of the plurality of access floor panels and/or to the tongue connectors of the second set of the plurality of access floor panels before the inserting step.
 14. The method of forming an access floor assembly according to claim 13, further comprising the step of honing top surfaces of the floor finish layers to remove any excess adhesive after the inserting step.
 15. The method of forming an access floor assembly according to claim 12, wherein the plurality of access floor panels are placed on the understructure members such that the four edges are directly supported by the understructure members. 